I just completed my project and first placed two frozen soda bottles inside. I did this in my garage here in south florida. The ambient temp is 94 degrees in the garage. Within an half hour the inside temp was 67 degrees.

I brought chiller inside with ambient temp of 79 degrees. I set thermostat to 64 degrees and it dropped to that in about five minutes.

I just did a little test so far, but I think I could easily get temps down in the 40's.

This is just a quick note. Thanks to this board for all the great info.

yeah good idea if youre in FL. are you really able to keep the temp in the 40s consistently without needing to be home all day filling it with ice or frozen water bottles? the best thing about fermentation chillers isn't that they keep the primary cold necessarily, in my experience, but that they soften the temperature swings during the fermentation. the best thing by far is a fridge which is what i'm going to get when i can convince the wife that the marginally higher electric bill will be worth it.

I am having no problems keeping at 64 right now. I really don't need to go much lower. I think this will work out better then a chest freezer and temp controller. I spent about 45 dollars on project, and that included a twenty dollar digital thermostat.

I am hoping to get at least 24 hours before changing bottles. I am doing a test tonight to see how long they go. I will be brewing my first brew (American Brown Ale) Sunday.

oh. so you haven't even fermented a beer yet? you'll soon see you can't keep the temp constant without refrigeration. unless you happen to have a cave, or can be home every few hours to put ice or bottles in the bath. i've tried, but good luck with that